In general, there is a related art image forming apparatus in which a supporting member (drawer case) that arranges and accommodates a process cartridge or cartridges can be withdrawn and removed from the apparatus main body. According to this structure, it is possible to easily handle paper jams when they occur and exchange process cartridges by removing the supporting member.
However, the exchange of the process cartridge can be performed even in a state in which the supporting member is withdrawn from the apparatus main body. Thus, a lock member for restricting the removal of the supporting member is provided on the supporting member or the apparatus main body so that the supporting member may not be removed and dropped during the exchanging operation. According to the related art, the lock member is provided on both sides of the supporting member one by one.